In the heart of the recession, the United States became a coupon-crazy country, clipping, printing and downloading billions of coupons a year.

That's still true, but the coupon industry is rapidly evolving, attracting younger users and more men, as well as zapping out more digital and mobile versions of the classic cents-off paper coupon.

"Years ago, coupons were mostly for grocery items, like cereal. Now it's almost everything you're buying, from clothes to restaurants to drugstores," said Jeanette Pavini, household savings expert with Coupons.com.

Last year, the number of manufacturers' coupons issued — for everything from diapers to dog food — was a staggering 305 billion. That's a lot of coupons to be clipped, printed or downloaded.

Yet the number of coupons actually cashed in by U.S. consumers in 2012 slipped 17 percent compared with the previous year, according to NCH Marketing Services in Deerfield, Ill., which tracks annual coupon usage.

While paper coupons clipped out of the Sunday paper still dominate, digital coupons on websites, mobile phones and retailers' loyalty cards are attracting a younger — and increasingly male — audience. At the same time, manufacturers are offering more nonfood coupons, which may affect demand.

Despite the recent dip, coupon usage is still well above what it was before the recession, according to NCH data.

"There's a large segment of the population that's made it part of their shopping habit," said Brown. "Overall, the consumer has maintained a frugal mind-set that was established during the recent economic downturn."

That comes as no surprise to "frugal bloggers" like Ashley Thompson, 29, of Sacramento, Calif., who got hooked on couponing after college as a way to pinch pennies.

Thompson, who posts at NorCalCouponGal.blogspot.com, says couponing crosses all ages, incomes and genders. "It's not just a female-centered phenomenon anymore. More men are conscious about (spending). It spans a whole spectrum, from minimum wage to those who make hundreds of thousands a year."

The couponing craze was fueled partly by TV shows like "Extreme Couponing" and savings-minded bloggers, websites and workshops.

As the recession eases off, consumer attitudes may be adjusting, said Darrel Ng, who has been blogging about Sacramento-area restaurant news and deals on his CowtownEats.com site.

"People have moved from finding the absolute cheapest deal to finding the most value," said Ng, noting the shift in his site's online traffic since 2009. Whereas two years ago a $2 beer might have been the most popular deal on CowtownEats, today it's higher-end offers, such as website coupons for $30 three-course dinners at some of the city's priciest restaurants.

Also factoring into the mix are so-called online "daily deal" sites, like Groupon, Living Social and Dealsaver, which have sprouted — and withered — at a fast pace. (Dealsaver is owned by the McClatchy Co., The Sacramento Bee's parent and a partner in McClatchy-Tribune News Service.)

Last year, more than 140 new daily deal sites popped up; at the same time, another 560 globally shut down, according to Daily Deal Media, which tracks the industry.

Ng feels they've "peaked and oversaturated" the market. "They aren't as good as when they first started. The quantity of deals is much bigger but it's questionable if you want them or not."

Boyan Josic, Daily Deal Media's founder and CEO, said the crowded daily-deal marketplace has contributed to a bit of "coupon fatigue," especially when companies that are bought, sold or merged sell their subscriber lists. Suddenly, a consumer who signed up for a local deal site is getting bombarded with unsolicited email offers from other companies.

Last year, about 90 percent of the 305 billion coupons issued were in print, either newspaper inserts or stand-alone mailers. While digital made up less than 1 percent of all those coupons, it accounted for more than 6 percent of the 2.9 billion that were cashed in, according to NCH Marketing.

Experts say consumers will be seeing more of that, such as coupons loaded directly onto store loyalty cards. Other retailers are experimenting with offers that pop up on smartphones as you pass by their door.